Fourier Series Coefficient Calculator

Understanding Fourier Series

What is a Fourier Series?

A Fourier series represents periodic functions as sums of sinusoidal functions.

f(x) = a₀/2 + Σ(aₙcos(nωx) + bₙsin(nωx))

where:

  • a₀/2 is the constant term
  • aₙ are cosine coefficients
  • bₙ are sine coefficients
  • ω = 2π/T (angular frequency)
  • T is the period

Fourier Coefficients

Constant Term (a₀)

a₀ = (2/T)∫f(x)dx

  • Average value over period
  • DC component
  • Mean of function

Cosine Terms (aₙ)

aₙ = (2/T)∫f(x)cos(nωx)dx

  • Even symmetry
  • Phase information
  • Amplitude scaling

Sine Terms (bₙ)

bₙ = (2/T)∫f(x)sin(nωx)dx

  • Odd symmetry
  • Frequency components
  • Harmonic content

Properties and Applications

Convergence

  • Uniform convergence
  • Gibbs phenomenon
  • Rate of convergence
  • Dirichlet conditions

Signal Processing

  • Frequency analysis
  • Filtering
  • Compression
  • Modulation

Special Properties

  • Parseval's theorem
  • Orthogonality
  • Symmetry relations
  • Energy distribution

Advanced Topics

Complex Form

  • Exponential series
  • Complex coefficients
  • Polar representation

Extensions

  • Fourier transform
  • Discrete series
  • Wavelets